SEOUL, Oct. 31 (Yonhap) -- Presidential candidates and political parties squared off Wednesday over extending South Korea's voting hours on polling day, which could affect turnout and the outcome of the race to pick the country's next chief executive in December.

The long-drawn debate has pitted liberal presidential hopefuls and political parties against the ruling Saenuri Party and its standard bearer Park Geun-hye.

Park and Saenuri said the voting hour issue should be reviewed by parliament, but there is a need to weigh the extra cost with benefits. The National Election Commission (NEC) claimed extending the voting period by a few hours will cost taxpayers around 10 billion won (US$9.1 million), while some critics claimed extending voting hours will not automatically lead to higher turnout.

The main opposition Democratic United Party (DUP), minor Progressive Justice Party and campaign managers working for independent contender Ahn Cheol-soo all urged extending the voting time to allow more people to exercise their voting rights.

Liberals want the current 6 a.m. to 6 p.m. voting window to be extended by two or three hours.

DUP spokesman Park Yong-jin said while Saenuri has questioned the validity of spending more money to extend voting hours, such claims miss the point of the debate entirely.

"Spending more so people can cast their ballots is a worthwhile move regardless of how much money is spent," he said.

He pointed out that in the past Saenuri did not oppose former Seoul Mayor Oh Se-hoon, who spent 16 billion won on a referendum to determine if people wanted free lunch at school, or the 20 billion won that Seoul will spend this year to tally votes from Korean nationals living abroad. The DUP wants to extend voting hours till 9 p.m.

Park added that an announcement by a Saenuri official earlier in the day, hinting that the party will be open to talks on enhancing voting rights, is a step in the right direction that needs to be pursued immediately.

The party's presidential hopeful Moon Jae-in also said that if Saenuri agrees to extend voting hours, he will accept a bill proposed by the conservative party that calls for returning state money given to political parties that field a candidate for the Dec. 19 election.

At present, a political party that fields a presidential candidate is entitled to election subsidies proportional to how many seats it has in parliament, but it is not obliged to return the money if its contender quits midway through the race.

"Moon has said the DUP will accept the bill forwarded by Saenuri, so it is our hope that progress will be made on the voting hours issue," Rep. Jin Sun-mee said.

This view was echoed by Ahn's spokeswoman, lawyer Jeon Yeon-soon, who said extending the voting hours depends entirely on the will of Park because she is holding the key.

"It is not right to talk about extra cost when the debate is about allowing more people to vote," she said.

The lawyer also said that a report by the National Assembly Budget Office showed it will cost the government just 3.1 billion won more to extend voting hours by two hours.

"Park has said she seeks '100 percent national unity,' but is it right to restrict the voting time to 6 p.m., which could deprive many people the right to vote because they cannot get off work by then?" the spokeswoman said.

The Unified Progressive Party also joined the attack by claiming 64 percent of 8.4 million non-regular workers will be unable to vote because they get off work too late. It added that extending voting hours will help raise South Korea's voting average for the national election from 63 percent, which is much lower than the Organization for Economic Cooperation and Development's average of 73 percent.

In response, Saenuri said calling for a voting rights extension with 49 days remaining before the Dec. 19 polls is a sign that the opposition party and Ahn is trying to use the debate as a political ploy.

"They never once mentioned this in the past, when there was plenty of time to carry out an objective debate," said Lee Jung-hyun, the head of the Saenuri candidates' public relations office.

The party said South Korea has gone to great lengths to ensure people can exercise their right to vote by making election day a public holiday and expanding absentee balloting across the board. Only Australia and the Philippines designate election days as holidays, while many countries hold their votes on Sunday.

It added that while the OECD voting number is higher than South Korea, this includes countries that make voting mandatory.

"If these countries are not counted, South Korea's voter turnout is actually high," a party official said.

Political pundits, meanwhile, said the ongoing dispute is widely regarded as a conflict of interest between conservatives and liberals. Liberals, whose supporters are mainly young, generally vote late, while older generation who are conservative in their political orientations, vote early.

"Because this year's election will likely be very close, any gains in turnout could affect results," a political observer said.

He added the voting hour issue could be used by the liberal side to consolidate their support ahead of the polls.

Some liberal groups are using Facebook to call for the extension of voting hours, with others planning to hold candlelight vigils in the coming weeks to urge change.

Meanwhile, the Saenuri Party plans to announce political reform measures later this week, including greater nationwide participation in party affairs, reform of the lawmaker nomination system and changes to the state prosecutors' office, according to a party official.

"Our party's presidential candidate Park will announce the reform measures in person," Ahn Dai-hee, the chief of the party's special committee for political reform, told Yonhap News Agency.

Ahn said the reform measures will be announced over several weeks, adding that various issues are being discussed.